The present invention relates to a machine for the manufacture of composite filters.
Conventionally, the harmful effects of inhaling cigarette smoke are reduced by tipping cigarettes with composite filters, that is to say with filters obtainable by pairing together two or more filter plugs made of material having different filtration characteristics.
In the case of composite filters incorporating two filter plugs, for example, these are prepared employing machines in which first and second plugs dispensed from separate reservoirs are transferred along a direction transverse to their longitudinal axes, by respective trains of fluted rollers, onto a common take-up roller with peripheral flutes.
Each flute will therefore accommodate a single filter element consisting of two axially aligned plugs having different characteristics.
These composite filter elements, made up of plugs placed in end-to-end contact, are then transferred by rotary transfer means onto a garniture tongue and fashioned into a filter rod. Proceeding singly and in succession on the tongue, more exactly, the filter elements advance in end-to-end contact along a direction parallel with their longitudinal axes and are wrapped in a strip of paper material to form a continuous filter rod.
The rod is divided up subsequently into single composite filters by a rotary cutter operating at the outfeed end of the garniture tongue.
In reality, these machines of conventional type for manufacturing composite filters betray serious limitations in terms of production speed.
More precisely, it has been found that they are not able to match the output speeds generated by cigarette makers and filter tip attachment machines of the latest generation, and therefore cannot be linked up directly to these same machines.
The object of the present invention is to provide a machine for manufacturing composite filters, such as will be unaffected by the above noted drawback.
A further object of the invention is to provide a machine for making composite filters, which in the event of a change in production size, that is to say in the length of the composite filter, will be able to guarantee that the filters are correctly positioned on the garniture tongue.